High decibel horns or sirens are used on trains and ships as a warning that the vehicle is approaching. When the horn is mounted to an outside of the structure in which crew or passengers are located, the sound propagating from the horn as well as the vibration generated by the horn is partially transmitted sideways to the structure and can be disturbing to the crew or passengers after prolonged exposure to the sound or vibration.
Usually, the horns or sirens are mounted to the structure of the vehicle or vessel with some sort of vibration absorbing member to absorb the primary high amplitude mechanical vibrations coming from the horn. Such vibration absorbing mountings serve to prevent damage to the structure as a result of the vibration.